138806 has 4 divisors (see below), whose sum is σ = 208212. Its totient is φ = 69402.

The previous prime is 138799. The next prime is 138821. The reversal of 138806 is 608831.

138806 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

138806 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34700 + ... + 34703.

It is an arithmetic number, because the mean of its divisors is an integer number (52053).

2¹³⁸⁸⁰⁶ is an apocalyptic number.

138806 is a deficient number, since it is larger than the sum of its proper divisors (69406).

138806 is an equidigital number, since it uses as much as digits as its factorization.

138806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69405.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 138806 is about 372.5667725388. The cubic root of 138806 is about 51.7769041804.

The spelling of 138806 in words is "one hundred thirty-eight thousand, eight hundred six".